Nutritionists Lyssie Lakatos and Tammy Lakatos Shames say to aim for a bar with no more than 220 calories and a maximum of 15 grams of sugar. “Even bars labeled as ‘low sugar’ contain sugar alcohols, which can wreak havoc on the digestive system, causing bloating and even diarrhea,” they warn.

Look for at least four to six grams of protein and five grams of fiber.

If you find yourself in a pinch, the right energy bar can be a convenient meal replacement as long as the calories and amount of sugar are kept under control.

Fitness expert Sarah Toland suggests looking for a meal-replacement bar that is around 300 calories, and contains at least 20 grams of protein and 5 grams of fiber. Also, keep the sugar to less than 20 grams.

Many energy bars have a nutritional label a mile long, full of artificial ingredients and junk, says Toland. “Instead, look for bars with short lists of recognizable ‘real-food’ ingredients like seeds, fruit or even whey protein.”

“When you can see and pronounce all the ingredients the bar is made of, you know exactly what you’re eating,” adds the Nutrition Twins.

Anthony Flynn, owner of You Bar, a create-your-own energy bar company, says you can taste the difference between a bar that is all-natural and a bar that is mostly artificial.

“People aren’t really concerned about the fat content when they know it’s coming from healthy ingredients like nuts and seeds.” Almonds, flax seeds, chia seeds, walnuts and cashews are the most popular ingredients.

Also, look for protein derived from pea, hemp or egg whites, he adds.

Avoid the processed bars with hydrogenated oils. They offer very little nutritional value, while setting you back in terms of health.

Toland adds that even when choosing healthier bars, you should definitely not be eating more than one of these bars a day, and you should avoid them right before bedtime. “Real, whole food is always preferable.”